How to spot a fake or copycat browser extension before you install it

Fake extensions copy the name, icon and description of a popular extension, or pretend to come from a well-known brand, to get installed. Some just show ads. Others read the pages you visit, change search results or collect data. They're usually easy to spot if you know where to look. Here are seven checks that take less than a minute.

1. Who published it?

Look at the publisher name (or developer name) under the extension title. An official extension from a brand is published by that brand, using its company name and usually with a link to its own website. A "Grammar Checker for Grammarly" published by an unknown individual is not from Grammarly, however similar the icon looks.

The Chrome Web Store and Firefox Add-ons also show badges for established, reviewed or recommended publishers. A missing badge doesn't prove anything is wrong, but a badge is a good sign.

2. Does the website match?

Real extensions link to their maker's website. Open it. Is it the company's real domain, or a lookalike such as grammarly-app.net or a free page builder site? Does the website link back to the same store listing? If it links to a different listing, you've found the copy.

3. Compare the user count

A famous extension with millions of users has a copy with a few hundred. If you find two listings with the same name and icon, the one with far more users and reviews is almost always the original. Search the store for the name and look at every result, not just the first one.

4. Read the reviews, especially the recent bad ones

Sort by newest. Reviews that say "this isn't the real one", "it changed my search engine" or "full of ads" are warnings. Be suspicious of a listing with many short, five-star reviews posted around the same time.

5. Check the permissions

Before installing, the browser shows what the extension may access. A screenshot tool that wants to "read and change all your data on all websites" may need it, but a calculator or a new-tab wallpaper doesn't. Permissions that are much broader than the extension's job are a reason to stop.

6. Look for copied or clumsy descriptions

Copycats often paste the original's description, sometimes with the brand name swapped, broken formatting or awkward wording. Search for a distinctive sentence from the description: if it appears on another, older listing, one of them is a copy.

7. Watch out for lookalike names

Names like Dark Reaber, G00gle Translate or Officiai use swapped letters to look right at a glance. So do words like "official", "pro" or "plus" bolted onto a famous name. Read the name letter by letter.

Already installed something suspicious?

1. Remove it from your browser's extensions page: chrome://extensions, edge://extensions or Firefox's Add-ons and themes page.
2. Check that your search engine and home page are what you expect.
3. If you entered passwords while it was installed, change them, and turn on two-factor sign-in.
4. Report the listing to the store so other people don't install it. Our guide to reporting copycat extensions shows where to find the report option in each store.

Quick checklist

• The publisher is the real company or developer.
• The website is the real domain and links back to this listing.
• The user count and reviews match the extension's reputation.
• Recent reviews don't warn about fakes, ads or hijacking.
• The permissions fit what the extension does.
• The description isn't a pasted copy of another listing.
• The name is spelled exactly right.

You can also look up any extension in the broext catalogue to see its publisher, users and other listings with the same name across Chrome, Edge and Firefox.